when we had our bathroom done, they fitted the bath first, then tiled around it and the sink unit

the toilet was floor and wall tiled first before the toilet as fitted over the top of it

when we had our kitchen done, they tiled the floor first, then put the stuff in, then tiled between the units

it also depends on if you have a seperate toilet and bathroom like we do, or if you have a bath/toilet together like many of the newer builds